Slide-changing mechanism.



lo. 7|2,03'4. Patnted Oct. 28, |902. M. BERGER.

SLIDE CHANGING MEcHANlsll.

(Application led .Tune 10, 1902.)

(No Model.)

2 Sheets-.Sheet I.

No. 7|2,o34. Patented oct. 2a, |902.v

M. BERGER.

SLIDE CHANGING MECHANISM.

(Application led June 10, 1902.) (No Model.) 2 Shets-Sheet 2L TH: NoRmsFermi co., m01 ouwe.. wAsHmGTnN. o. c.

UNrrnfD STATES PATENT OFFICE, y

MAX BERGER, OF JENA, GERMANY, ASSIGNOR TO FIRM OF CARL ZEISS, OF

JENA, GERMANY.

SLIDE-CHANGING MECHANISM.

SPECIFICATION forming part of Letters Patent No. 712,034, dated October28, 1902.

Application filed June 10, 1902. Serial No. 110,986. (No model.)

.T a/ZZ whom, t Wz/a/y concern:

Be it known that I, MAX BERGER, engineer, a subject of the King ofSaxony, residing at Carl Zeiss Strasse,.lena,in the Grand Duchy ofSaxe-Weimar,GermanEmpire,haveinvented a new and useful Slide-ChangingMechanism, of which the following is a specification.

Duplex slide-carriers for projection apparatus were hitherto made in theform of slid- 1o ing double frames carrying consecutively (in thedirection of the sliding movement) two slides. When these double framesare guided horizontally', the slide outside the cone of light (the slideawaiting exchange) is in turn on one and the other side of the cone oflight, which condition is inconvenient and entails in the case ofthelargerl models of apparatus separate attendance on each side-z'. e.,requires two persons. This drawback is obvizo ated in the verticalmovement where the slides to be interchanged are either above or belowthe cone of light. The vertical sliding movement is, however, but rarelypracticable on account of lsufficient space below 2 5 the cone of lightnot being usually available.

The duplex slide-carrier constructed according to the present inventionneither has the disadvantage peculiar to the horizontal double frame noris it subject to thelimited 3o applicability of the vertical doubleframe. Two separate carriers are arranged lin two different planes atright angles to the axis of the cone of light. Each carrier is capableof such (sliding or revolving) movements that 3 5 one may be within thecone of light while the other is in the outside position, allowing theslide to be exchanged, and vice versa. Either the objective or eachcarrier is adjustable in the direction of the cone of light between two4o stops, so that at each change of carriers the normal distance betweenobjective and slide may easily be restored. The two carriers may beconnected in such a way that by a single impulse one or other is put inoperative position and the one previously in use put out of the cone oflight. An arrangement for shifting automatically the objective or thetwo carriers in either direction, so as to reestablish the correctdistance between 5o objective and slide, may be combined with themechanism for operating the carriers.

Figure 1 is a side elevation of aisliding duplex carrier combined with ashiftable objective. Fig. 2 isasection on line 2 2 in Fig.

1. Fig. 3 is a section on line 3 3 in Fig. 1. 55 Fig. 4 is a sideelevation of a revolving duplex carrier combined with a fixed objective.Fig. 5 is a section on line 5 5 in Fig. 4:. Fig. 6 is an enlargedsection on line 6 6 in Fig. 5.

The duplex slide-carrier and the objective 6o shown in Figs. l to 3 areadjustable along the rail a. Two guide-rods b and c, parallel t-o therail a, are fitted to two uprights e and f,

rising from the adjustable bracket d and acting as stops in shifting theobjective h, which slides by its foot g along the rods b and c. In theupper portion of a second adjustable l bracket 1l the two slidingcarriers 7c and L are guided. For the sake of simplicity the carriersare represented as adapted for slides of 7o horizontal pattern only,being provided withl rectangular openings m and n and grooves 0 and pfor inserting the slides. While the slide in carrier Z is beingexhibited, (in proximity lto the illuminating-lens (1,) carrier 7c is 75in the inoperative position and its slide is being changed.

The carriers are changed kby pushing carrier la inward and withdrawingcarrier Z. The distance between the objective hand the slide 8o in thecarrierlc is then too short by the amount of the distance vbetween thetwo carriers. Therefore the objective must be moved away an equaldistance-namely,till its foot g comes in contact with the stop e.

In the arrangement illustrated by Figs. 4 to 6 the objective h is fixedupon its bracket d. lThe two carriers le and Z are movably connectedwith the bracket t" by means of their arms fr and s. They are providedwith 9o openings m and n and with. grooves o and p', also with knobs tand u, for the convenience of handling. As shown in Fig. 6, the brackett" is fitted with an axle o, having two short screw-grooves w and a; ofequal but opposite pitch. The extremities of the carrierarms r and s aretted as sleeves on the axle v and engage by the pins y and e' into thegrooves zu and of this axle. The length and pitch of these grooves aresuch that each of roo the two carriers may make a revolution of ninetydegrees, undergoing at the same time a displacement in the direction ofthe rail a equal to the distance between the two carriers. The drawingsshow carrier Z' in operation and carrier 7o inactive.

To change the carriers, the knob t is seizedand carrier 7c screwed upinto the operative position. Simultaneously, by reason of the axialpressure oif arm 7" upon arm s, carrier Z' is automatically screwed intothe inoperative (lower) position. The carrier 7c by its helical movementarrives at exactly the saine position previously occupied by carrier Z',so that the objective h needs not to be shifted.

It will be understood that in the example Figs. 4 to 6 stops for easilyrestoring the distance between the objective and the slide when thecarriers are changed are applied analogous to the objective stops e andfin the first example. In the second example these stops arecarrierstops and consist in the end walls of the helical grooves w andx. They confine the displacement of the carriers in the direction of thecone of light and by reason of the peculiar combination of thecorrecting displacement with the changing movement proper also theirrevolution.

What I claim as my invention, and desire to secure by Letters Patent,is-

l. In a projection apparatus the combination with two separateslide-carriers arranged in different planes at right angles to the axisof the cone of light and movable so as to be simultaneously one in andthe other out of the cone of light, of means for restoring the distancebetween the slide and the objective, when the carriers are changed, suchmeans comprising a set of stops, which confine the relative displacementbetween the carriers and the objective, essentially as described.

2. In a projection apparatus the combination with two separateslide-carriers arranged in different planes at right angles to the axisof the cone of light and connected together so as to be moved by thesame impulse one into and the other outof the cone of light, of meansfor restoring the distance between the slide and the objective, when thecarriers are changed, such means comprising a set of stops, whichconfine the relative displacement between the carriers and theobjective, essentially as described.

3. A duplex slide-carrier comprising two separate carriers arranged indiiferent planes at right angles to the axis of the cone of light andconnected together so as to be moved by the same impulse, one into andthe other out of the cone of light, and both in the direction of thecone of light for restoring the proper distance between the slide andthe objective, and a set of stops confining the movements of thecarriers,essentially as described.

In testimony whereof` I have signed my name to this specification in thepresence of two subscribing witnesses.

MAX BERGER.

Witnesses:

EMIL DNi'rZ, PAUL KRGER.

